[gnumeric] PythonLoader: use more modern python ref handling.

[Morten Welinder <mortenw src gnome org>]

commit 21464b296d9244360e7f5aa7c66bf1af7dca171f
Author: Morten Welinder <terra gnome org>
Date:   Sun Mar 21 22:02:20 2021 -0400

    PythonLoader: use more modern python ref handling.

 plugins/python-loader/gnm-py-interpreter.c | 9 ++-------
 plugins/python-loader/py-gnumeric.c        | 3 +--
 plugins/python-loader/python-loader.c      | 8 +++-----
 3 files changed, 6 insertions(+), 14 deletions(-)
---
diff --git a/plugins/python-loader/gnm-py-interpreter.c b/plugins/python-loader/gnm-py-interpreter.c
index ccc3d9e86..b921bd0a3 100644
--- a/plugins/python-loader/gnm-py-interpreter.c
+++ b/plugins/python-loader/gnm-py-interpreter.c
@@ -60,10 +60,7 @@ gnm_py_interpreter_finalize (GObject *obj)
 {
        GnmPyInterpreter *interpreter = GNM_PY_INTERPRETER (obj);
 
-       if (interpreter->stringio_class != NULL) {
-               Py_DECREF (interpreter->stringio_class);
-       }
-
+       Py_CLEAR (interpreter->stringio_class);
        parent_class->finalize (obj);
 }
 
@@ -161,9 +158,7 @@ run_print_string (const char *cmd, PyObject *stdout_obj)
                if (PyFile_WriteObject (v, stdout_obj, Py_PRINT_RAW) != 0)
                        PyErr_Clear ();
        }
-       if (v) {
-               Py_DECREF (v);
-       }
+       Py_XDECREF (v);
 }
 
 void
diff --git a/plugins/python-loader/py-gnumeric.c b/plugins/python-loader/py-gnumeric.c
index e0892d3df..af4b5fc7d 100644
--- a/plugins/python-loader/py-gnumeric.c
+++ b/plugins/python-loader/py-gnumeric.c
@@ -852,8 +852,7 @@ py_gnumeric_shutdown (void)
        if (GnmModule) {
                // At least clear the module.  We leak a ref somewhere.
                PyDict_Clear (PyModule_GetDict (GnmModule));
-               Py_DECREF (GnmModule);
-               GnmModule = NULL;
+               Py_CLEAR (GnmModule);
        }
 }
 
diff --git a/plugins/python-loader/python-loader.c b/plugins/python-loader/python-loader.c
index 1ca96287f..10fc3512c 100644
--- a/plugins/python-loader/python-loader.c
+++ b/plugins/python-loader/python-loader.c
@@ -242,8 +242,8 @@ gplp_func_file_probe (G_GNUC_UNUSED GOFileOpener const *fo, GOPluginService *ser
                probe_result = PyObject_CallFunction
                        (loader_data->python_func_file_probe,
                         "O", input_wrapper);
-               Py_DECREF (input_wrapper);
        }
+       Py_XDECREF (input_wrapper);
        if (probe_result != NULL) {
                result = PyObject_IsTrue (probe_result);
                Py_DECREF (probe_result);
@@ -335,8 +335,7 @@ gplp_load_service_file_opener (GOPluginLoader *loader,
                loader_data = g_new (ServiceLoaderDataFileOpener, 1);
                loader_data->python_func_file_probe = python_func_file_probe;
                loader_data->python_func_file_open = python_func_file_open;
-               if (python_func_file_probe != NULL)
-                       Py_INCREF (loader_data->python_func_file_probe);
+               Py_XINCREF (loader_data->python_func_file_probe);
                Py_INCREF (loader_data->python_func_file_open);
                g_object_set_data_full
                        (G_OBJECT (service), "loader_data", loader_data,
@@ -787,8 +786,7 @@ gplp_unload_service_function_group (GOPluginLoader *loader,
        GO_INIT_RET_ERROR_INFO (ret_error);
        loader_data = g_object_get_data (G_OBJECT (service), "loader_data");
        SWITCH_TO_PLUGIN (go_plugin_service_get_plugin (service));
-       Py_DECREF (loader_data->python_fn_info_dict);
-       loader_data->python_fn_info_dict = NULL;
+       Py_CLEAR (loader_data->python_fn_info_dict);
 }
 
 typedef struct {